Other observers describe America's judges as conservative or liberal, implying they bring an ideology to their decision-making that goes beyond a careful assessment of law and precedent. That view has made the U.S. Senate's confirmation of federal judges fraught, with each party battling to block nominees they view as unsympathetic to their positions.

But is there any evidence politics plays a role in judicial opinions? An Associated Press review suggests it might.

The AP looked at opinions by nearly 40 federal district court and appellate judges about Trump's ban on travelers from mostly Muslim countries. It found only one judge nominated by a Democratic president has supported Trump's authority to keep out all travelers or deport those who arrived just as the first ban took effect. With some exceptions, Republican nominees have taken a broader view of presidential power and rejected limits on the executive orders.